CDM 2015 welfare cleaning requirements on construction sites

What CDM 2015 says about welfare facilities

The Construction (Design and Management) Regulations 2015 place legal duties on clients, principal designers, principal contractors, contractors, and designers across all notifiable construction projects. For principal contractors, the welfare duties are set out primarily in Schedule 2 of the Regulations, and supported by the HSE's welfare guidance for construction sites.

Schedule 2 requires principal contractors to provide and maintain:

• Sanitary conveniences (toilets) — adequate number for the workforce, separated by sex or individually lockable, ventilated, lit, and kept clean
• Washing facilities — including showers where work is particularly dirty or involves exposure to hazardous substances; hot and cold (or warm) water; soap and towels (or dryers)
• Drinking water — readily accessible, clearly marked as drinking water
• Changing rooms and lockers — where workers have to wear special clothing and cannot reasonably be expected to change elsewhere
• Rest facilities — with means to warm food and boil water, seating with tables, and protection from bad weather

The word "maintained" in Schedule 2 is significant. Facilities must not simply be provided — they must be kept in working order, adequately stocked (soap, paper, hot water), and in a clean and orderly condition throughout the construction phase. This is an ongoing obligation, not a one-time installation requirement.

How many welfare facilities does a construction site need?

CDM 2015 does not specify exact ratios, but the HSE's welfare guidance provides practical numbers based on the maximum number of people on site at any one time. These are minimum requirements — the principal contractor should always provide more where the nature of the work demands it.

Number of workers on site	Minimum toilets	Minimum washbasins
1–5	1	1
6–25	2	2
26–50	3	3
51–75	4	4
76–100	5	5

On projects with a mixed workforce of men and women, the above figures apply to each sex separately — unless the site uses individual lockable cubicles (combined toilet and washbasin), in which case the ratios can be applied to the total workforce.

The key point: welfare provision is calculated on peak occupancy, not average daily attendance. If a site regularly peaks at 60 workers during key construction phases, it needs 4 toilets and 4 washbasins available during those phases — even if the average daily attendance is lower.

Construction dust and COSHH — why HEPA vacuums matter

One of the most commonly misunderstood aspects of construction site cleaning is dust control. The HSE's guidance on construction dust identifies three main types of hazardous dust on construction sites: silica dust (from cutting, grinding, or drilling stone, concrete, and masonry), wood dust (from machining or sanding wood), and lower toxicity dusts (general construction dust from other materials).

Silica dust is classified as a Group 1 carcinogen by the International Agency for Research on Cancer. Prolonged exposure causes silicosis — an incurable and progressive lung disease — and increases the risk of lung cancer. The COSHH Regulations 2002 require employers to prevent or adequately control workers' exposure to silica dust, including controlling dust at the point of generation and using effective dust extraction equipment.

For post-construction cleaning — whether of welfare facilities during the build, or the final sparkle clean before handover — standard vacuum cleaners and dry brushing re-circulate fine dust particles into the air rather than capturing them. Only HEPA (High Efficiency Particulate Air) filtered vacuum equipment can capture particles small enough to include respirable silica — rated H class (EN 60335-2-69) for the finest particles.

This is why specifying HEPA vacuum equipment in a construction cleaning specification is not an optional enhancement — it is a COSHH compliance requirement when post-construction cleaning involves disturbing settled construction dust.

What to include in your Construction Phase Plan for welfare cleaning

On notifiable projects, the principal contractor must prepare and maintain a Construction Phase Plan (CPP) before construction begins. The CPP must include arrangements for managing the project, including welfare arrangements. In practice, the welfare section of many CPPs is generic and vague — which creates problems when HSE inspects and asks to see the plan.

A robust CPP welfare section for a project that will last more than a few weeks should include:

• The number and type of welfare facilities to be provided, and where they will be located on the site
• The welfare cleaning contractor's name, and their cleaning schedule (frequency per week, which facilities covered)
• How welfare consumables (soap, paper, hot water) will be restocked and who is responsible
• How welfare facility condition will be monitored and recorded (daily inspection by site manager, or by the cleaning contractor)
• The arrangements for the post-construction sparkle clean before handover

Naming the welfare cleaning contractor and their schedule in the CPP transforms welfare cleaning from an informal arrangement into a documented programme — which is exactly what HSE expects to see when they inspect. If an improvement notice is issued for inadequate welfare, the principal contractor can demonstrate that a cleaning programme was in place and show the inspection records. Without documentation, there is no defence.

How Vigil structures welfare cleaning contracts for London construction sites

Vigil provides construction site welfare cleaning across Greater London on programmes typically running from 12 to 24 months, aligned to the build timeline. Our approach:

• Site assessment first: We visit the site before agreeing any programme. We review the CDM welfare plan, assess current and peak worker headcount, and inspect the welfare facilities to determine appropriate cleaning frequency by area and occupancy level.
• Programme-aligned contract: Your welfare cleaning contract is structured against your build programme — not against a calendar. We flex frequency and scope as the programme progresses.
• CDM documentation support: We provide a written welfare cleaning specification that can be incorporated into your Construction Phase Plan, and digital visit records after every clean that are formatted for site diaries, HSE inspections, and handover packs.
• HEPA sparkle cleans: The sparkle clean before practical completion is included in your programme contract, timed against your handover date. We use HEPA H-class equipment as standard, with a written sign-off report for your handover documentation.

Because all Vigil operatives are directly employed, DBS checked, and COSHH-trained before deployment to any site, you have a documented supply chain for your welfare cleaning that can withstand HSE scrutiny and client audit.